diff --git a/src/Decoder.c b/src/Decoder.c
index 62b7cad..267eb32 100644
--- a/src/Decoder.c
+++ b/src/Decoder.c
@@ -1096,7 +1096,7 @@ static void ZydisSetOperandSizeAndElementInfo(ZydisDecoderContext* context,
         case ZYDIS_INSTRUCTION_ENCODING_3DNOW:
         case ZYDIS_INSTRUCTION_ENCODING_XOP:
         case ZYDIS_INSTRUCTION_ENCODING_VEX:
-            if (operand->mem.type != ZYDIS_MEMOP_TYPE_MEM)
+            if (operand->mem.type == ZYDIS_MEMOP_TYPE_AGEN)
             {
                 ZYDIS_ASSERT(definition->size[context->eoszIndex] == 0);
                 operand->size = instruction->addressWidth;